Traffic signal



Feb. 23, 1937A. l|| J, SMITH f 2,071,955

` 4 TRAFFIC SIGNAL Filed Jan.. 6, 1952L 3 Sheets-S1186?l 1 kol TroRNYs Feb. 23, 1937.

H. J. SMITHA TRAFFIC S IGNAL Filed Jan. 6, 1932 3 Sheets-Sheet 2A.

n u 0 A@ .m Y l INVENTOR Feb. 23, 1937. H. J. SMITH TRAFFIC SIGNAL Filed Jan. 6, 1952 3 Sheets-Sheet 3 f ,A fw

TToRNEYs Patented Feb. 23, 1937 UNiTED sr PArENT OFFICE This invention relates to an automatic'trafc signal such as now commonly used at the intersection of two or more streets or other thoroughfares to direct traffic. Such vsignals have com- 5 monly been provided with colored illuminated means usually of redor rgreen color, to indicate respectively Stop and Go for the trailic. been foundin practice that with such signals it is very diflicult at times to tell which way the signal stands until the driver is very close to it. In cases of fog and at other times when the sun shines on the signal, the driver often cannot tell which way the signal stands until he is too close upon it to properly controland stop his car.

It is an object of this invention, therefore, to provide an automatic traffic signalhaving a signal element preferably of the 'illuminated type which is movable and can thus'be seen from a long distance even in foggy and rainy` weather, and no matter how the light mayshine thereon.

It is a further object of the invention to provide a signal having as a traffic indicating element a rotating arm carrying at one end a signal element such as an illuminated means. It is still another object of the invention to provide an automatic traine signal having as a trac directing element for one street a stationary illuminated means and having as the traffic directing element acting simultaneously for the other street a rotating element preferably comprising lamps disposed at opposite ends of an arm or 'axis and rotating with said arm or about said axis. Y

It is also an object of the invention to provide an automatic trac signal'of the self-contained type having motor driven means for changing the signal for the respective thoroughfares and having a clock mechanism for actuating an escapement'for determining the periods of actuation.

And a further object is to provide a rotatable Stop-Go traic signal wherein willbe incorporated various features and characteristics constituting novel andimproved structure both as individual kentities of the traic signal and in combination with each other. v

With the above objects in View, as well as others which will appear as the specification proceeds,

:the invention comprises the construction, ar-f It has sible as long as within the spirit of the invention and the scope of the claims which follow.

In the accompanying drawings forming a part of this specication,

Fig. 1 is an elevational view of a trafc signal made according to the invention;

Fig. 2 is an elevational view of a modied type of trame signal having the features of the invention;

Fig.'3 is a View disclosing a fragment of the traic signal of Fig. 2, the parts being shown in a different position;

Fig. 4 is an elevational View of a further modiiied type of traffic signal made according to the invention;

Fig. 5 is an enlarged plan view of the traiic signal of Fig. l, the hollow steel member and the upright or post being removed;

Fig. 6 is an elevational view of the disclosure of Fg;

Fig. 7 is a detail sectional view taken on line l-'l in Fig. 6;

Fig. 8 is a detail sectional view taken on line li---l in Fig. 7;

Fig. 9 is a detail sectional view of an adjusting tool for the traffic signal;

Fig. l is a detail sectional View taken on line IU--Ill in Fig.

Fig. 11 is a vertical sectional view detailing features of the disclosure of Fig'. 6, a part of the upright or post being shown;

Fig. 12 is a vertical sectional View of the portion of the traiic signal which is above the portion thereof shown in Fig. 11; v f

Fig. 13 is a detail sectional View taken as on line l3-I3in Fig. 12; Y Y

Fig. 14 is a detail sectional View taken as on line |4`I4in Fig. 12;

Fig. l5 is an elevational View of the upper portion or rotary lamps of the traflic signal as seen from the left in Fig. 12;

Fig. 16 is an enlarged vertical sectional View of the clock mechanism of the traflic signal;

Fig. 17 is a horizontal sectional View taken as on line Il-I'l in Fig. 16; and Fig. 18 is a wiring diagram.

With respect to the drawings and numerals of reference thereon, a non-tipable, metallic subbase for supporting the trafc signal is represented at 26. A base 2l proper of the traine l signal is attached to the sub-base, as by screw bolts 22, the base 2| constituting a portion of a frame in and upon which working parts of the traffic signal are mounted.

An electric motor 23 is suitably supported upon the base 2|, and the shaft of the motor 23 carries a worm 24 which meshes with a worm wheel 25 freely rotatable, but fixed against longitudinal movement, upon a vertical shaft 26 suitably mounted in the frame which includes the base 2l Numeral 21 denotes ball-bearings for the vertical shaft 26.

A clutching member 28 is supported by the lower surface of the worm wheel 25, and a complemental clutching member 29 is splined to the vertical shaftr26 at position below the clutching member 28 to be movable longitudinally upon said vertical shaft, toward and away from the worm wheel 25. A retaining nut 39 is supported upon the lower end portion of the vertical shaft 26, and.

a coil spring 3l about a portion of the clutching member 29 is seated between said retaining nut 30 and said clutching member 29 to urge this clutching member toward the clutching member 28. It will be obvious that when the clutching members 28 and 29 are in engagement and the motor 23 is operating, the vertical shaft 26 will be rotated, the worm 24 driving the Worm wheel 25, said worm wheel 25 driving the clutching members 28 and 29, and said'clutching member 29 driving said vertical shaft 26. vIt will also be obvious that when the clutching members 28 and 29 are separated, as shown in Fig. 6, the driving connection between the motor 23 and the vertical shaft 26 will be broken.

The Vertical shaft 26 passes upwardly through a top plate 32, and the portion of said vertical shaft directly above the'top plate xedly carries a pinion 33. The pinion 33 meshes with a large gear 34 which is rotatably mounted in the top plate 32, and said gear 34 iixedly'rcarries an upwardly extending, centrally disposed member 35 including undulating cam surfaces 36. An angular member 31 extends upwardly from the center of the member 35. Said angular member 31 removably'supports an upright or post 38, as shown more clearly in Figs. 11 and 12, and said post 38 in turn supports the signals of the traflic signal in a manner to be hereinafter fully set forth.

It should be here remarked that the ratio of the pinion 33 to the gear 34 is 1 to 4, so that upon one complete revolution of the worm wheel 25, and with it the pinion 33, said gear 34 makes one-quarter of a revolution. In practice, the arrangement is such that the clutching members 28 and 29 are each time engaged to cause the pinion 33 to make one complete revolution, and upon termination of said complete revolution said clutching members 28 and 29 become disengaged. 'Ihe traificsignal includes mechanism for causing said clutching members to be again engaged, after each disengagement thereof, upon the terminationfof an interval of time predetermined by a clock mechanism with escapement.-

Of ,Y said clock mechanism', which is as disclosedsupported upon the base 2|, numeral 39 representsV a main spring having its outer end anchored at 49 to Athe frame and its inner end attached, as at 4l, to the main shaft 42 of the clock mechanism, said main shaft extending upwardly through the cover 43. Gearing 44 associates the main spring 39 with an escapement 45 in usual manner, and 46 represents the balance wheel of the clock mechanism.

An extension shaft 41 attached to the main shaft 42 is suitably mounted in the top plate 32 and projects upwardly beyond said top plate. A pair of spaced apart, horizontal, interrupted gears, denoted 48 and 49, of insulating material are mounted upon the extension shaft 41 below the top plate 32 to be freely rotatable upon said extension shaft and slidable longitudinally thereof. The toothless periphery of each of the interrupted gears 48 and 49 carries contact strips, designated 59 and 5I, respectively, and said contact strips, 59 and 5l are in engagement with a conducting strip 52 which is insulatively mounted, as at 53, upon a member 54 fixed toV a vertically reciprocable rod 55. The rod 55 is slidably mounted, as at 56, in a bracketattached Vto the base 2l, and in the top plate 32, as at 51, and the upper end of said rod 55 includes an elbow 58 which carries a roller 59 ridable upon the cam surfaces 36. See Figs. 5, 6 and l1. The interrupted gears 48 and 49 with their contact strips 5I!l and'5l, together with the conducting strip 52, the member 54 and the rod 55, constitute a unit of the traffic signal. The member 54 supports a shipper arm 69 having its outer end arranged in a groove 6| which is attached to the lower interrupted gear 49 in such manner that said interrupted gears 48 and 49 will move upwardly and downwardly with the rod 55 as this is moved upwardly and downwardly by travel of the cam surfaces 36 relatively to the roller 59 in a manner to be hereinafter explained.

The contact strips 59 and 5I are adapted to be engaged by a brush 62.carried at the lower end of a conducting springV arm 63. Said conducting spring arm 63 is insulatively attached, as at 64, to a segment 65 which is fixed upon the extension shaft 41 above the top plate 32. A shaped conducting piece 66 is Vattached to the conducting spring arm 63, as at `61',`a;ndf-the`upper. end of said conducting piece 66 iixcdly` carries a hub 68 which isV insulatively carried by the upper end of the extension shaft 41. 'Ihe arrangement is such that when Athe extension shaft 41 is caused to rotate, the hub 68,' the shaped conducting piece 66, the segment 65, and the conducting spring arm 63 rotate therewith as a unit to cause the brush 62 to travel over the upperinterrupted gear 48 with contact strip 50, or `the lower interrupted gear 49 with contact strip 5I, as the case may be at a particular time, depending upon whether the roller 59 is upon a high or a low part of the cam surface 36.

The lower clutching member 29 carries a cam finger 69 which is normally engaged by a lever member 10 to separate said clutching member 29 from the clutching member 28, as these parts are shown in Fig. 6. The lever member 19 is pivotally supported upon the frame, as at 1I, and includes an integral arm 12 to the outer end of `which a coil spring 13 is attached, the opposite end of said coil spring being attached to the frame at 14. Obviously, the coil spring 13 urges an end portion of the lever member 16 toward the cam finger 69. lA pin 15 fixed upon Vthe frame limits the extent to which the coil spring 13 can swing the arm 12, and hence limits the distance the lever member 19 can swing in direction toward the cam finger 69. member 10 includes a cut away portion 16 which is shapedas more clearly shownin Fig. 10. Upon rotation of the clutching member 29 in the direction of the arrow in Fig. 5, the cam linger 69 rides against the cut-away portion, from the position as shown in dotted lines to the position as shown in full lines in Fig. 10, to thus be depressed and to in turn depress the lower clutching member 29 against the action of the coil spring 3l to vrelease said clutching member 29 from the clutching member 28. Numeral 11 rep- The leverV of a small gear 81.

resentsa desirably vertical surface of the lever member 18 at one end of the cut-away portion 16 which is normally engaged by the cam ringer 69 to preclude rotation ahead of the lower clutching :member 29 beyond the position in which shown in Fig. 5, as will be understood.

Mechanism is provided for precluding rotation yof thevcam finger 69 and the clutching member -back of the cam finger 69, about as shown in Fig. 5, but is adapted to be swung outwardly, against the action of the coil spring 88, when struck by said cam nger 69 during the later stage of each complete revolution of the clutching member 29 occurring after release of the cam finger 69 fro-m the'lever member 18,V by mechanism now to be described. Said releasing mechanism includes a solenoid 82 suitably fixed upon the pivoted lever member 18 and having an armature 83. vThe armature 83 is adapted to move inwardly of the solenoid upon energizationk thereof, and pivotally supports, as vat 84,'one end portion of an actuating link 85. The opposite end portion of saidactuating link-85 is eccentrically pivoted, as at 86, to an outer portion An inner part of said small gear 81 is pivotally attached, as at 88, to said pivoted levermember 18. A coilspring 89, secured to the actuating link 85 and to the lever -member 18, normally holds the parts in about lwith the teeth of the worm wheel 25. Upon engagement of the teeth of the small gear 81 with the teeth of said worm wheel 25, said small gear 81 is caused, by advancement of the teeth of said worm wheel, to complete a revolution, and, evidently, as the Wider side of said eccentrically mounted small gear 81 moves to positionbetween the small gear axis 88 and the worm wheel 25, the lever member 18 is swung outwardly upon its axis 1| and against the action of the coil spring 13. The arrangement here is such that said lever member 18 is caused to beswung a sufficient distance to release the stop 11 from the cam nger 69, to thus allow the clutching members 28 and 29 to engage under the action of the coil spring 3l. Obviously, upon release of the cam finger 69 by the lever member 18, said clutching member 29 is free lto complete a revolution. In practice the cam nger 69 is adapted to engage the stop 11 of the lever member 18 upon the completion of each revolution in the manner as already described and as clearly shown in Figs. 5 and 10.

An insulating ring 98 is suitably secured to the clutching member 29 to rotate therewith, and said insulating ring conveniently supports a contact strip 9| which extends almost the full distance about the insulating ring, but is broken at 92 to provide a dead spot. A brush 93 engages the contact strip 9| and is adapted to lie at the dead spot 92 when the parts are positioned as in Figs. 5 and 6.

Referring to Fig. 18, numerals 94 and 95 represent incoming lead wires, the former being attached to the conducting strip 52, and the latterv being attached to the electric motor 23. A lead wire 96 extends between said electric motor 23 and the solenoid 82, and a lead wire 91 extends lbetween said solenoid and a conducting strip 98 insulatively supported upon the top plate 32 as at 99. Said conducting strip 98 is suitably attached-to the conducting hub 68. See Figs. 5 and 11.

Suppose'the parts of the trafl'lc signal as thus far described to be positioned as disclosed in Figs. 5 and 6, with the contact brush 62 out of engagement with either of the contact strips 58 or 5| while the clock mechanism is operating step by step, under the influence of the escapement 45, and that eventually said contact brush 62 is rotated to position to engage one of said contact strips 58 or 5|. Instantly, the solenoid 82 is energized, the circuit through said solenoid being traced from the incoming wire 94 through the conducting strip 52 and the appropriate contact strip- 58 or 5| to the contact brush 62, thence `through the elements 63, 66, 88 and 98 and. the

lead Wire 91 to the solenoid 82, and thence through the lead wire 96 and the motor 23 back to the incoming wire 95. Upon venergization of the solenoid 82, the armature 83 is attracted to rotate the` small gearl 81 in the manner as already explained to cause said small gear to engage the teeth of the worm wheel 25. Evidently, the worm wheel 25 is set into operation at the same instant the solenoid 82 is energized, the solenoid circuit and the electric motor circuit being connected in series, and advancement of said worm wheel causes the lever member 18 to be released from the finger 69 in the manner as already set forth, the clutching members 28 and 29, as a consequence, becoming engaged. Thence the electric motor 23 will drive the worm wheel 25 to cause the clutching member-29 to complete one revolution, and the pinion 33 will also, evidently, complete a revolution and rotate the gear 34 and the angular member 31 through one-quarter of a revolution.

The upper end of the vertical shaft 26 xedly carries a crank arm |88 which pivotally supports a link |8| having an elongated slot |82 arranged in its outer end portion and extending longitudi-l nally of the link. The segment 65 xedly carries an upstanding pin |83 which is arranged in the elongated slot |82. When the parts are posi.- tioned as in Fig. 5, the pin |83 is situated in an inner portion of said elongated slot |82 about as shown, but upon actuation of the clock mechanism under the control of the escapement as hereinbefore set forth, the segment 65 andthe pin |83 rotate with the shaft extension 41, in the directionv of the arrow in Fig. 5, to carry said pin |83 toward the outer end of saidelongated slotr |82. The crank arm |88 naturally makes a` complete revolution each time the pinion 33 revolves through 360, so that during the earlier stages of actuation of said pinion 33 in the manner as explained, the link |8| is drawn toward the left in Fig. 5 to reset the clock mechanism, it being understood that during each rotating actuation of the traic signal through an arc of the clock mechanism is wound up precisely the amount it was caused to run down during the irnmediately preceding period While the traiic signal was in set, stationary position. During the later stages of actuation of the pinion 33, the link |8| is moved back to the position as in Fig. 5.

spots,` each high-,spot ,bei

In order to give the signal more accurate timing, it is essential that there be no lost motion in the winding ratchet of the clock mechanism, and this result canv be secured by placing said winding ratchet upon the secondary shaft of-the'escapement. It will be apparent that any other type 4of self-starting escapement, even an electrical type, can be substituted for the escapement disclosed.

The partsof thetraiic signal are shown in Figs. 5 and 6 as when the link |0| has actuated the pin v|03 and the brush 62 to Ythe fully wound Yposition ofthe clock mechanism and has itself moved to position allowing said clock mechanism to operate under the control of the escapement to rotate the extension shaft 41 in Ythe manner as already set forth, to thus cause the brush 62 to rotate in direction to eventually engage one of the contact strips-50 or 5|, and the pin |03 to move outwardly in the slot |02. When the brush 62 comes into engagement with one of the contact strips 50 or 5I, the pin |03 has reached approximately the termination -of its travel toward the `outer end of the elongated slotv |02. Upon-said brush 62 coming into contact with one of theY contact strips 50 or 5|, the electric motor 23 and the solenoid 82 are energized, and the clutching member 29 and the crank arm |00 are-caused to travel through a complete revolution, said crank arm |00 actuating the link |0| to reset the eXtension shaft 41 at the position as shown in Figs. 5 and 6, with the pin |03 and the brush 62, naturally, moved back to their original positions, said brush-being out of contact with either of the contact strips 50 or 5|.

Evidently, therbrush 62 will disengage the contact strips 50 and 5| during the period before the clutching member 29 has made a complete revolution. 'Ihus the circuit includingthe solenoid l82 and the electric motor 23 will be broken and said solenoid will be de-energized. But said electric motor 23 must remain energized to cause said clutching member 29 to complete its revolution which will position the dead spot 92 of the insulating ring adjacent the brush 93. To this end, a lead wire |06 connects the incoming wire 94 with the contact strip 9|, and a lead Wire |05 connects the brush 83 with the lead wire 06, so that the motor circuit is traced from the incoming wire 9@ through the lead Wire; lill!- to the contact strip S i, and thence through the brush 93, the lead wires |05 and 96, and the electric motor 23 back tothe incoming Wirex95. Y

v Mechanism is provided formaintaining the interrupted gear 38 with Contact strip 50, and the interrupted gear i9 with contact strip 5|, in stationary position, and for separately adjusting each interrupted gear with contact strip about the extension shaft d'1, in order that the Contact strips 50 and 5| can beV independently set at preferred locations relatively to the initial position of the `brush 62. That is to say, it Vmay be desirable to set the traflicV signal at Stop positionV upon a street for a longer or ashorter period than said traic signa-l is set at Go position upon said street. It should be here stated-that theV cam surfaces 36 include twooppositely disposed highspotsand two oppositely-V disposedlow asfaltweg@ at-99nd-- spess@ t when 'j D; Evidently p H0 are VThat is to say, by reference to the calibration H3,`

,alternately employedto- Ienergize the-.solenoid ,B2

,and the electric motor 23, one of saidcontact stripscooperatingvvith the b rush V62 tocontrol `.the interval the signal is set at .Stop position for a street, andthe other of said contactstrips cooperating with said brush to control the interval said-signal is set-at vGo position for said street. Obviously, the contact strip v50 or `5| which cooperatesin controlling the Stop interval at a street cooperates vin controlling the Go vinterval at an intersecting street, andthe contact `strip 5| or 50 which cooperates incontrolling the Go interval -at a street cooperates in controlling the Stop interval at an intersecting street.

The interrupted gear 48 is engaged in Vits toothed. portion by a pinion |06, and the interrupted gear 40 is engaged Yin its toothed-portion byapinion |01. The pinion |01 is fixed upon-a vertical `spindle |08 which issuitably mounted Vupon the frame, and a compression spring |09 engages said spindle |08 to steady its action. The pinion l 06 is carried by a sleeve ||0 which is suitably mounted in the frame and upon the spindle |08, and a compression spring engages said -sleeve ||0to steady its action.` A tool ||2 has jone Vof itsend portions constructed to adjust- -v ably rotate the spindle |08 independently of the sleeve I0, and its other end portionconstructed to rotatably adjustl the sleeve H0 independently Vozf the spindle I 08. Thus the'interrupted gears 48 andl49 are not only retained in stationary position after adjustment, but can be independently adjusted to situate the contact strips '50 and 5|, respectively, at any desired position relatively to Vthe set position of the brushvGZ, as will be underi stood. In Fig. 8'there is disclosed-'a calibration, denoted ||3, which represents seconds, with respect to which the spindle 08 and the sleeve independently, rotatably adjustable.-

Veach ofthe contact strips'50 and 5| can be independently adjusted so that any desired and predetermined period of time, measured in seconds.

kas illustrated, can elapse between the instant .when the brush 62 is initially set, as in Figs. 5 and 6,"and the instant when said brush 62 reaches position to engage the contact strip which is at the particular time at the elevation of the brush.

The trac signal includes a hollow steel cover member ||4 which is attached to the base 2|. as by screw bolts H5, providing a housing for the motor 23, the solenoid 82, etc., said cover member fil including a cylindrical Vupright VH6 which surrounds the upright or post 38 in spaced relation thereto. An upper -portion vof the upright Vor post V38 is xedly attached, as at H1, to a Vdownwardly extendingV rectilinear frame H8. Said frame IIB includes tWo oppositely disposed faces each having the lword Go thereon and two oppositely disposed faces each having the word Stop thereon, said faces being arranged Y90" apart. It will be understood that upon each quarter turnrof the angular member 31, the upright orpost 38 will be advanced-to rotate the 4signals 90.

Ahorita-.fraught Post S--Suiiablrnnd rigidly Ysurvxpo s, @Sak-H3.' d

,rectilinear framea|| 8- and the Stop and Go l sirably of metal, the open ends of said casing |24 as disclosed being arranged, facing in the same directions as the open portions of the frame ||8 which have Go thereon. The casing |24 conveniently supports a horizontal shaft |25 which fixedly carries a member |26 including oppositely disposed arms suitably carrying light bulbs |21 which are adapted to be constantly rotated Within said casing |24, numeral |28 yrepresenting a small electric motor conveniently supported within the casing |24 for rotating the member |26 with light bulbs |21. The motor shaft has a pinion |29 which meshes with a gear |39 fixed upon the shaft |25. It will be seen from the drawings that owing to the direct drive of arm |26 from motor |28 through gears |29 and |36 and from the respective sizes of said gears that arm |26 is rapidly rotated.

Electric current is supplied. to the light bulbs |22 and |21 and to the small electric motor |28 by means of lead wires |3| and |32 which are attached to the incoming wires 94 and 95, respectively, as disclosed. The lead wire |3| is attached to an inner brush |33 insulatively mounted within the cylindrical part ||6 of the hollow steel cover member |14, and the lead wire |32 is attached to an outer brush |34 also insulatively mounted within s-aid cylindrical part H6. The brushes |33 and |34 are conveniently supported upon the Wall of the part ||6. An insulating block |35 is conveniently mounted upon the upright or post 38 and Within the cylindrical part ||6 tof rotate with said upright or post. Said insulating block |35 supports an inner, circular contact member |36 which is engaged by the brush |33, and an outer, concentric contact member |31 which is engaged by the brush |34. Appropriate lead wires extend from the contact members |36 and |31 to the light bulbs |22 and the small motor |26. See Fig. l2. Also, appropriate lead wires extend from said contact members |36 Aand |31 to a pair of brushes |38 conveniently and insulatively supported within the casing |24, vand said brushes 133 carry electric current to the light bulbs |21 through the medium oi contact rings |39 suitably disposed upon the member |26 and lead wires extending from said contact rings |39 to said light bulbs |21.

It will be apparent that the casings |29 and |24 will be rotated step by step, along with the upright or post 36 and the Stop-Go frame ||8 as these are advanced step by step, as set forth, by the driving mechanism of the traffic signal. It will also be apparent that the bulbs |22 and |21 will always be lighted whenever the traic signal is in operation, and that the small motor |28 will be constantly energized to cause the light bulbs |21 to be continuously rotated. The opposite open ends of the casings |20 and |24 are desirably closed by transparent covers |110. In Fig. 1, |46 represents a green signalling element associated with each cover |40.

In Figs. 2 and 3 a modied type of traflic signal having the features of the invention is disclosed. The signal as there illustrated will be more appropriately employed to sumce for a single street. The operation of the present signal is substantially the same as the operation of the signal already described, except that the traffic signal of Figs. 2 and 3 is horizontally mounted, as at |4I, upon an ordinary street post |42.

In Fig. 4 there is disclosed an overhead cable |43 which supports a housing |34 for working mechanism of the traic signal, which working mechanism may be substantially the same as already described. A flexible shaft |45 in the present type of signal displaces the post 38 and suspends the signals proper from the housing |43 which is itself suspended from the cable |43. The present signal operates in practice in essentially the same manner as the signal disclosed in Fig. 1 and as already fully described.

What I claim is:

1. A tranc signal unit adapted to be disposed at the intersection of two thoroughfares and vadapted to direct traffic to go on one thoroughfare and stop on another having in combination, a vertically extending member, means for mounting said member for oscillation through 90 degrees at the end of regular and Vdeiinite periods, a casing carried by said member having open opposite ends, an arm rotatable about its center in said casing, illuminated means at each end of said arm visible at both ends of said oasing, means for constantly rotating said arm and illuminated means without relation to said periods, said rotating arm and illuminated means constituting a go signal for traic, a second oasing adjacent said casing carried by said member having opposite open ends directed at right angles to said ends of said lirst mentioned casing, illuminated means in said second casing visible at both ends thereof and constitutingl a stop signal.

2. A traffic signal unit adapted to be disposed at the intersection of .two thoroughiares and adapted to direct traic to go on one thoroughfare and stop on another having in combination, a member, means for mounting said member for oscillation through 9G degrees at the end 'of regular and deinte periods, a go signal unit comprising a casing carried by said member having open opposite ends, an arm rotatable about its center and about a horizontal axis substantially at the center of said casing, a lamp at each end of said arm, means for illuminating said lamps, means` for constantly rotating said arm without relation to said periods, transparent means in the ends of said casing so that said rotating lamps are visible at both ends of said casing; a second casing having open opposite ends directed at 90 degrees to said first mentioned ends, lamps in saidsecond casing, means for illuminating said last mentioned lamps, said last mentioned lamps being visible at each end of said second casing and constituting a stop signal whereby said casing with said rotating lamps therein may be alternately directed to said thoroughfares.

HENRY J. SMITH. 

